RESUMO
Opening the porphyrin macrocycle of pheophorbide a and forming the primary fluorescent chlorophyll catabolites are key steps in the chlorophyll catabolism pathway. These steps are catalyzed by pheophorbide a oxygenase and red chlorophyll catabolite reductase (RCCR). In this study, a novel RCCR gene, CaRCCR, was isolated from the pepper (Capsicum annuum L.). The full-length CaRCCR complementary DNA is comprised of 1173 bp, contains an open reading frame of 945 bp, and encodes a 314-amino acid protein. This deduced protein belongs to the ferredoxin-dependent bilin reductase family. Amino acid sequence alignment showed that CaRCCR shared a high homology to other higher plant RCCR proteins. CaRCCR expression, as determined by quantitative real-time polymerase chain reaction, was higher in the leaves than the roots, stems, flowers, and immature fruits. CaRCCR expression was almost constant during all phases of leaf development. It was upregulated by abscisic acid, methyl jasmonate, and salicylic acid. Moreover, CaRCCR was induced by high salinity and drought stress treatments; it was also slightly regulated by Phytophthora capsici. Taken together, these results suggest that CaRCCR is involved in defense responses to various stresses.
Assuntos
Capsicum/enzimologia , Capsicum/genética , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/genética , Sequência de Aminoácidos , Capsicum/efeitos dos fármacos , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Dados de Sequência Molecular , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Proteínas de Plantas/química , Alinhamento de Sequência , Análise de Sequência de DNA , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genéticaRESUMO
Molecular chaperones of plasmid pBI121 carrying CaMV35S promoter and a nucleotide sequence of plasmid pBI221 were inserted into plasmid pCAMBIA2300 to construct an intermediate vector: pVBG2307. This novel vector pVBG2307 contains a greatly expanded multiple cloning site with an adjacent imported CaMV35S promoter sequence. This vector allows controlled transformation of DNA in both Escherichia coli and Agrobacterium tumefaciens. Cloned PG, orf456, ipt genes and E8, a fruiting promoter, were amplified by PCR of cDNA libraries of Capsicum annum and Lycopersicon esculentum and were then transferred into vector pVBG2307. The viability of this vector was demonstrated, as it regulated PG, orf456, ipt and E8 genes in E. coli and could be transferred into Agrobacterium strain EHA105-4.